The broad objective of this proposal is to quantitatively evaluate in dynamic terms the intrinsic propulsive performance of intestinal regions of cats and to examine how this performance is controlled by interactions among neural and myogenic subsystems intrinsic to the intestine, the fluid load being propelled and extrinsic control systems. The areas of particular interest are: a) fluid propelling capability of intestinal segments into an attached evaluation system having negligible resistance and constant capacitance, b) fluid propelling capability into an evaluation system having significant input resistance and infinite capacitance, c) propulsive behavior when conditions associated with the evaluation system vary as functions of time, properties resulting from the propulsion process, or both, d) the ability of hormone and extrinsic neural inputs to modulate propulsive performance, e) alterations of propulsive states by transmural stimulation, and f) interactions among intestinal wall motions, muscle mechanics, and propulsive behavior. The general method of approach will be to measure, in vitro, the amount of fluid propelled from the oral and aboral ends of an intestinal segment into an attached propulsion evaluation system which imposes on the segment well-defined physical conditions and permits the amount of propulsive work done in propelling a given fluid volume to be determined.